New DAF Euro6 engine
DAF Trucks has announced a new Euro6 Paccar MX-11 engine generation for buses and coaches. The new engine is compact and designed to offer optimum fuel efficiency, low weight and noise levels combined with excellent performance and maximum durability. The new power unit has a displacement volume of 10.8-litres and is scheduled to go into production in September 2013. There will be five different ratings available for two main application areas. The 290hp, 330hp and 370hp versions with maximum torques of 1,200, 1,400 and 1,600Nm respectively (at 1,000–1,650 rpm) are intended for urban, express and national PCV applications. For long distance coaching, there will be the 400hp and 440hp ratings, which are available with maximum torques of 1,900 and 2,100Nm respectively (at 1,000–1,450 rpm).
DAF’s Paccar MX-11 has a completely new design. It is made of strong compact graphite iron, with vertical ribs to maximize strength and achieve low noise levels. As many functions as possible have been integrated to maximize reliability and durability. The double overhead camshafts are a key feature of the new cylinder head, which has four valves per cylinder and an integrated inlet manifold, which DAF claims offers significant advantages. The power unit uses an advanced common rail system, which allows high injection pressures of up to 2,500 bar and provides the opportunity to use pre and post-injection or a combination of both. According to the manufacturer, this results in finer fuel atomization and many more opportunities to optimize combustion to ensure the lowest possible emission and noise levels, as well as better fuel efficiency.
The fact that the temperature of the exhaust gases can be controlled so effectively also means the engine can be optimally integrated with the exhaust gas after-treatment system. A turbocharger with variable geometry (VTG) is used, which should ensure the engine can call on the best turbo settings at all times and across its entire speed range in order to deliver maximum performance. The EGR system is compact and designed for an optimum mixture of exhaust gases and fresh air. In order to meet Euro6, DAF is using various exhaust gas after-treatment technologies such as an SCR catalytic converter and an active soot filter. The new Paccar MX-11 engine features numerous innovations, such as a single poly V-belt and an energy saving air compressor.